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<h3><a name="SECTION0019133000000000000000">
17.1.3.3 Replacing os.system()</a>
</h3>

<p>
<div class="verbatim"><pre>
sts = os.system("mycmd" + " myarg")
==&gt;
p = Popen("mycmd" + " myarg", shell=True)
sts = os.waitpid(p.pid, 0)
</pre></div>

<p>
Notes:

<p>

<ul>
<li>Calling the program through the shell is usually not required.
</li>
<li>It's easier to look at the <tt class="member">returncode</tt> attribute than
      the exit status.
</li>
</ul>

<p>
A more realistic example would look like this:

<p>
<div class="verbatim"><pre>
try:
    retcode = call("mycmd" + " myarg", shell=True)
    if retcode &lt; 0:
        print &gt;&gt;sys.stderr, "Child was terminated by signal", -retcode
    else:
        print &gt;&gt;sys.stderr, "Child returned", retcode
except OSError, e:
    print &gt;&gt;sys.stderr, "Execution failed:", e
</pre></div>

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